Re: "Who Killed the Electric Car?" opens July 14th

On Tuesday, in article <e77fnu$64m$1@xxxxxxxxxxxxxxxxx>
nospam@xxxxxxxxxx "Paul Ciszek" wrote:

In article <ts08921rcopiukhoc3vs7ius8gn48v9iqv@xxxxxxx>,
Michael Benveniste <mhb-offer@xxxxxxxxxxxxxx> wrote:
On Sat, 17 Jun 2006 04:36:39 +0000 (UTC), nospam@xxxxxxxxxx (Paul
Ciszek) wrote:

Of course, that's a false either-or. India is committed to Thorium
reactors. The desirable isotope of Thorium is also the most common
(so no isotope separation); the reaction produces only as many
neutrons as it consumes, making it dependent on an outside neutron
source (no possibility of a runaway chain reaction); and none of
the products are useful in making fission weapons.

Not quite.

Any reaction which produces only as many neutrons as it consumes
would not be sustainable, as neutrons would inevitablely make
their way out of the system.

That is a feature, not a bug. The design is called a "subcritical
energy amplifier"; before someone jumps on me for claiming to violate
the first law of thermodynamics, the energy comes from fission, and
it isn't really amplification in that sense. I will give two
sources now, then go on with the description:

http://doc.cern.ch/archive/electronic/cern/preprints/lhc/lhc-96-001.pdf
http://www.inesap.org/bulletin17/bul17art25.htm
Also wiki on "energy amplifier" and "Carlo Rubbia"

You make neutrons through spallation, by hitting a target with
high energy protons. Yes, this is an added complexity that conventional
reactors don't have, but it also means that you have complete control
over the rate at which fission takes place, by modulating the proton
beam current. The reactor is designed to produce between 0.95 and
0.98 neutrons for each one consumed; for each neutron introduced
into the core, twenty to fifty fission events should take place.
Shut off the proton beam, and you shut off the fission.

I don't remember seeing mention of this tech on the Atomic Rockets
website (at www.projectrho.com/rocket/index.html), which is a great
resource for all that Fifties-style sci-fi space-opera. And it has that
slightly off-the-wall feel to it. It sounds like the sort of nuclear
reactor a slightly naive writer would use to make a story work--
"Captain, the proton beam's failed. We've no power!"--but it's real.

I think it's the sort of thing, competently written-up, that would be
worth getting on the site. And it's vaguely reminiscent of Kipling's
airship stories too.

Me, I'm thinking of Space:1889 and the (very difficult) potential
invention of atomic energy available in that setting. A thorium reactor,
with no need for the exotica of isotope seperation, would fit nicely in
that sort of steampunk world.

--
David G. Bell -- SF Fan, Filker, and Punslinger.

"I am Number Two," said Penfold. "You are Number Six."
.

Relevant Pages

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